“The Accidental Victim” is a title that sounds like a John le Carré spy thriller. The book by James Reston Jr. is not fiction but the just-released profile of John Fitzgerald Kennedy’s presumed assassin is as taut as any spy thriller.

In the 50th anniversary year of JFK’s death, many writers have been busy with retrospectives and analyses of the murkiness around the event, including the widely-held belief in conspiracy that will not go away 50 years later. Mr. Reston has top chops as a journalist, having authored 15 books. He has bored deep into the heart of events and movements and pastimes which he regards as his “eight obsessions.”

Mr. Reston has been chewing and writing on the assassination in Dallas for most of his adult life. Convinced that Lee Harvey Oswald acted alone, his goal here is to determine why Oswald did it. “Sometimes attacking a great and significant historical event from an oblique angle can lead to astonishing surprises,” Mr. Reston writes in his preface. “That was my experience here.”

Mr. Reston comes from a highly visible Island family. His father, James “Scotty” Reston, columnist, Washington correspondent, and executive editor of New York Times, purchased the Vineyard Gazette in 1968. His brother Richard Reston was the Gazette publisher from 1988 until its sale in 2010. He will discuss his book, slated for a September 9 release, at the Vineyard Haven Library on Wednesday, August 28, at 7 pm.

Mr. Reston’s research has led him to conclude in “The Accidental Victim” that Lee Harvey Oswald acted alone and that his intent was not to assassinate the 35th president but to shoot Texas Governor John Connally, who was seated next to the president in the presidential limousine as it drove slowly through the streets of Dallas. Mr. Connally was wounded in the attack but recovered.

His research includes close reading of the 889 pages of the 1964 Warren Commission report, interviews, and microscopic attention to the details of Oswald’s life and personality. The Warren Commission was convened a week after the JFK assassination to investigate the murder and to determine, among other things, whether Oswald acted alone or as part of a larger conspiracy.

A raft of conspiracy theories bobbed to the surface after the Nov. 23, 1963 presidential murder. Mr. Reston reasons that Mr. Oswald was a poorly-wired loser fueled by grandiosity and the loss of an honorable discharge from the U.S. Marine Corps. His discharge was reclassified retroactively as a dishonorable discharge following Mr. Oswald’s well-publicized renunciation of U.S. citizenship and his temporary relocation to Russia. Mr. Connally was the U.S. navy secretary when Oswald’s honorable discharge was downgraded.

Mr. Reston concludes that Mr. Oswald regarded his Marine Corps service as a shining success, perhaps the only real success he had ever had. And while books, movies, articles, and talk shows have had a flourishing industry for decades in treating conspiracy theories, which included Mr. Oswald as the shooter at someone else’s behest, Mr. Reston says that as an impassioned bumbler, Mr. Oswald would not be a prime choice as an assassin.

“This question lingers: Could Lee Harvey Oswald have been an agent of either state violence or mob violence?” Mr. Reston writes. “With such barely formed ideas, such grandiosity, such determined independence, Oswald was scarcely a good prospect to be recruited as an assassin by a foreign state or by the Mafia. If Cuba, the Soviet Union, or a big-time mobster had wanted to assassinate an American president, they had far more reliable instruments of violence than Oswald.”

In essence, Mr. Reston reasons, high school dropout Lee Harvey Oswald shot the wrong man. He was seeking to avenge his dishonorable discharge by killing John Connally. One Warren Commission witness, Carroll Jarnigan, recounted a meeting between Messrs. Jack Ruby and Oswald that was in fact an assassination conspiracy — to kill Governor Connally and open Texas to organized crime business. Jarnagin’s story failed a lie detector test and was dismissed by the commission.

Mr. Reston’s work here is noteworthy and important to me and, I imagine, to most readers who were stunned on Nov. 23, 1963, and confused and frustrated for years after by the Babel of hysterical conversation around the event. His conclusion has telescoped a vast landscape of information and opinions into a tight recounting based on the Oswald persona.

Essentially, Mr. Oswald is described as an unstrung attention-seeker without the ability to draw fame. Ironically, if Mr. Reston is correct in “The Accidental Victim’s” conclusions, Mr. Oswald finally became famous for an act he did not intend. His fame lasted two days when he was shot dead himself by Dallas barman Jack Ruby.

The book also puts the business of high-level security in a different perspective. Secret Service could trot beside a slow-moving convertible limousine carrying the president of the United States in 1963 because America was innocent, perhaps arrogant, or both. We did not believe we could be attacked.

Tragic ironies abound. The most tragic: absolutely no one around the president wanted him in Dallas, except JFK himself. Allowing East Coast liberals to motorcade in Texas is a lightly-regarded idea today and the idea was even more bizarre 50 years ago.

I would recommend a read of this book. Pay attention to the notes following the book text. You will understand the event and gain additional perspective on what it was like then, what happened, and what it’s like in America today.